Final answer:
The OTR is applying the intervention technique of Cognitive-Behavioral Therapy.
Step-by-step explanation:
The OTR in this scenario is applying the intervention technique of Cognitive-Behavioral Therapy. Cognitive-behavioral therapy is a psychotherapeutic approach that focuses on modifying beliefs and attitudes to promote adaptive behavior. In the context of post-polio syndrome and chronic pain management, cognitive-behavioral therapy can help the client develop coping strategies, challenge negative thoughts about pain, and make lifestyle changes to adapt to the condition and improve quality of life.